Substrate plating device

ABSTRACT

The present invention relates to a substrate plating apparatus for plating a substrate in a plating bath containing plating solution. An insoluble anode is disposed in the plating bath opposite the substrate. The substrate plating apparatus comprises a circulating vessel or dummy vessel provided separate from the plating bath, with a soluble anode and a cathode disposed in the circulating vessel or dummy vessel. An anion exchange film or selective cation exchange film is disposed between the anode and cathode and isolates the same, wherein metal ions are generated in the circulating vessel or dummy vessel by flowing current between the soluble anode and the cathode therein, and the generated metal ions are supplied to the plating bath. The substrate plating apparatus can also comprise an ion exchange film or neutral porous diaphragm disposed between the substrate and anode in the plating bath, wherein the ion exchange film or neutral porous diaphragm divides the plating bath into a substrate region and an anode region.

TECHNICAL FIELD

The present invention relates to a substrate plating apparatus forperforming a metal plating process on a substrate such as asemiconductor wafer.

BACKGROUND ART

FIG. 1 shows the general structure for this type of a conventionalsubstrate plating apparatus. As shown in FIG. 1, a substrate platingvessel 101 accommodates a plating solution Q. Disposed within thesubstrate plating vessel 101 are a substrate 102, such as asemiconductor wafer; an anode 103 positioned opposite the substrate 102;and a shielding plate 104 interposed between the substrate 102 and anode103. A power source 106 applies a predetermined voltage between thesubstrate 102 and anode 103 for forming a plating film on the surface ofthe substrate 102. A collecting gutter 105 is provided for collectingplating solution Q that overflows from the top end of the substrateplating vessel 101.

When suing a soluble electrode (have phosphorous copper) for the anode103 in the substrate plating apparatus described above, it is necessarynot only to regularly replace the anode but also to process black filmon the surface of the electrode and take measures for generatedparticles. Since this type of substrate plating apparatus is normallyprovided with a plurality of substrate plating vessels 101, upkeep ofthe anode 103 can be considerably time-consuming.

One method of attempting to correct these problems is to use an anodeformed of an insoluble material in the plate processing vessel. Whilethis material has the advantage of suppressing the existence ofparticles around the substrate 102, it gives rise to the necessity forreplenishing Cu²⁺ ions. Cu²⁺ ions can be added by supplying copper oxidepowder or CuSO₄—5H₂O powder, or by supplying a highly concentratedsolution of CuSO₄—5H₂O. However, supplying powder is not appropriate foran automated process. Further, adding a solution gradually increases theoverall amount of liquid, thus requiring that the plating solution beperiodically discharged.

To improve the uniformity of the plating film thickness formed on thesurface of the substrate 102 in the plating vessel described above, itis best to ensure that the primary current distribution between thecathode (substrate 102) and the anode 103 is uniform. One way to ensurea uniform distribution of the current is to increase the distancebetween the cathode and the anode 103. However, this requires a largersubstrate plating vessel 101, and consequently, a larger platingapparatus, which is contrary to the object of decreasing the size of theplating apparatus.

When the electrolytic plating conducted is copper plating, for example,the soluble anode often includes phosphorus copper. However, it isdifficult to manage the black film formed on the surface of this solubleanode, and the black film produces particle contaminants that can be alarge problem. This problem can be overcome by using an insoluble anode.However, insoluble anodes give rise to the problem of how to supply Cuions to the plating solution, as well as the problem of the additivedissolving and becoming deposited on the semiconductor wafer or othersubstrate.

DISCLOSURE OF INVENTION

In view of the foregoing, it is an object of the present invention toprovide a substrate plating apparatus employing an insoluble anode, andparticularly a substrate plating apparatus capable of easily andautomatically supplying metal ions.

It is another object of the present invention to provide a substrateplating apparatus capable of supplying a uniform primary currentdistribution between the cathode and anode and facilitating reduction ofthe size of the plating apparatus.

It is further another object of the present invention to provide aplating apparatus capable of preventing the substrate from beingcontaminated by particles produced from black film, even when using asoluble anode.

These objects and others will be attained with a substrate platingapparatus for plating a substrate in accordance with the presentinvention. The substrate plating apparatus comprises a plating bathcontaining plating solution. A substrate is disposed in the plating bathand serves as a cathode. A insoluble anode is disposed in the platingbath opposite the substrate. A circulating vessel or dummy vessel isprovided separate from the plating bath. A soluble anode is disposed inthe circulating vessel or dummy vessel. A cathode is disposed in thecirculating vessel or dummy vessel opposite the soluble anode. An anionexchange film or selective cation exchange film is disposed between theanode and cathode and isolates the same. And also provided is an ionreplenishing system for creating a current between the anode and cathodeto generate and supply metallic ions to the plating bath.

The substrate plating apparatus described above is constructed with acirculating vessel or dummy vessel separate from the plating bath, suchthat metal ions generated from the soluble anode in the circulatingvessel or dummy vessel are supplied to the plating bath. With thisconstruction, it is possible to supply metal ions automatically.Further, this construction eliminates the need to perform cumbersomejobs associated with conventional devices, such as regularly replacingthe anode in the plating bath and taking measures to treat black filmgenerated on the surface of the anode.

According to another aspect of the present invention, a substrateplating apparatus for plating a substrate comprises a plating bathcontaining plating solution. A substrate is disposed in the platingbath. An anode is disposed in the plating bath opposite the substrate.And, an ion exchange film or neutral porous diaphragm is disposedbetween the substrate and anode in the plating bath, wherein the ionexchange film or neutral porous diaphragm divides the plating bath intoa substrate region and an anode region.

The ion exchange film or neutral porous diaphragm provided between thesubstrate and anode serves to increase the electrical resistance of theplating solution, achieving the same effects as increasing the distancebetween the substrate and the anode. Accordingly, it is possible todispose the substrate and anode close together.

Further, the cation exchange film allows the passage of ions dissolvedfrom the anode and blocks impurities dissolved from the anode.Accordingly, the amount of particles in the plating solution in thesubstrate region can be greatly reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the general construction of a conventional substrateplating apparatus;

FIG. 2 shows a first embodiment of a substrate plating apparatusaccording to the present invention;

FIG. 3 shows another embodiment of a circulating vessel or dummy vesselused in the substrate plating apparatus;

FIG. 4 shows another embodiment of the substrate plating apparatusaccording to the present invention;

FIG. 5 shows a second embodiment of the substrate plating apparatusaccording to the present invention;

FIG. 6 is an explanatory diagram showing the effects of disposing apositive ion exchange film or neutral porous diaphragm between thecathode and anode in the substrate plating apparatus;

FIG. 7 is a cross-sectional view showing a detailed structure of asubstrate plating apparatus according to the second embodiment of thepresent invention;

FIG. 8 is a cross-section view showing another embodiment of thedetailed structure of the substrate plating apparatus;

FIG. 9 shows a third embodiment of a substrate plating apparatusaccording to the present invention;

FIG. 10 is an enlarged view of the area B in FIG. 9;

FIG. 11 shows another embodiment of a substrate plating apparatus; and

FIGS. 12A and 12B are a plan view and a side view respectively showingthe overall structure of the substrate plating apparatus employing theplating bath.

BEST MODE FOR CARRYING OUT THE INVENTION

A substrate plating apparatus according to preferred embodiments of thepresent invention will be described while referring to the accompanyingdrawings.

FIG. 2 shows an embodiment of a substrate plating apparatus according toa first embodiment of the present invention. The substrate platingapparatus includes a circulating vessel or dummy vessel 10 and aplurality (three in this embodiment) of plating baths 11. Each platingbath 11 contains a semiconductor wafer 12 that is the object of a copperplating process; an insoluble anode 13 disposed opposite thesemiconductor wafer 12; and a power source 15 connected between thesemiconductor wafer 12 and the anode 13.

The circulating vessel or dummy vessel 10 contains a dummy cathode 16; asoluble anode 17 formed of copper and disposed opposite the cathode 16;and an anion exchange film 18 disposed between the cathode 16 and anode17 for dividing the circulating vessel or dummy vessel 10 into a dummycathode side and an anode side. A DC power source 19 is connectedbetween the cathode 16 and anode 17. A conductivity analyzer 21 isprovided on the circulating vessel or dummy vessel 10 to measure theconductivity of the liquid contained within the circulating vessel ordummy vessel 10. Sulfuric acid (H₂SO₄) is supplied from a sulfuric acidsource 20 to maintain the liquid at a uniform conductivity.

By applying a DC voltage of a predetermined amount from the power source19, the anode 17 emits Cu²⁺ ions into the liquid on the anode side,while on the cathode side SO₄ ²⁻ negative ions and H₂ gas are generated.The H₂ gas escapes from the top of the vessel. The SO₄ ²⁻ ions passthrough the anion exchange film 18 and are supplied to the anode side,while the Cu²⁺ ions do not pass through the anion exchange film 18. Apump 22 pumps out the aqueous solution containing a mixture of Cu²⁺ andSO₄ ²⁻ ions. This solution is supplied as the plating solution to eachof the plating baths 11 via a plurality of on-off valves 23.

A collecting gutter 14 is provided on each of the plating baths 11 tocollect excess plating solution that overflows from the plating baths11. This excess liquid collected by the collecting gutter 14 is returnedto the anode side of the circulating vessel or dummy vessel 10. At thistime, the anode 17 replenishes the liquid with Cu²⁺ ions and the liquidis subsequently resupplied to each of the plating baths 11. In otherwords, the plating solution is supplied with Cu²⁺ ions to compensate forthe amount consumed in the copper plating process conducted in each ofthe plating baths 11.

In the plating apparatus described above, the sum of currents I₁, I₂,and I₃ flowing between the semiconductor wafer 12 and anode 13 of eachrespective plating bath 11 is set equal to a current I flowing betweenthe cathode 16 and anode 17 in the circulating vessel or dummy vessel 10(I=I₁+I₂+I₃). As a result, it is possible to supply to each of theplating baths 11 an amount of Cu²⁺ ions corresponding to the amountconsumed in the plating process. In addition, there is no longer a needto replace the anodes in the plating baths 11 regularly or to performbothersome measures or operations associated with the prior art toprevent contamination generated by black film on the surface of theanodes. Also in FIG. 2, a pump 24 is provided for discharging liquidfrom the circulating vessel or dummy vessel 10.

FIG. 3 shows another embodiment of a construction of the circulatingvessel or dummy vessel 10 employed in the substrate plating apparatus ofthe present invention. The embodiment in FIG. 3 differs from that inFIG. 2 only in that the anion exchange film 18 provided between thecathode 16 and anode 17 is replaced with a selective cation exchangefilm 25. The cation exchange film 25 allows the passage of H⁺ ions, butprevents the passage of Cu²⁺ ions.

With this configuration, the power source 19 applies a direct current ofa predetermined value between the cathode 16 and anode 17 and the pump22 supplies a plating solution containing Cu²⁺ ions emitted from theanode 17 to each of the plating baths 11 shown in FIG. 2 via theplurality of on-off valves 23. Plating liquid overflowing from each ofthe plating baths 11 is returned to the anode side of the circulatingvessel or dummy vessel 10, as described for FIG. 2.

FIG. 4 shows another embodiment of a substrate plating apparatusaccording to the present invention. In this substrate plating apparatus,one circulating vessel or dummy vessel 10 is provided for each platingbath 11. Liquid in the anode side of the circulating vessel or dummyvessel 10 as divided by the anion exchange film 18 or cation exchangefilm 25 is supplied to the plating baths 11, while plating solutionoverflowing from the plating baths 11 is returned to the anode side ofthe circulating vessel or dummy vessel 10.

The semiconductor wafer 12, serving as the cathode in the plating baths11, is connected to the anode 17 in the circulating vessel or dummyvessel 10, while the anode 13 is connected to the cathode 16. Connectingwires 27 and 28 are provided to connect the semiconductor wafer 12 andanode 17 and the insoluble anode 13 and cathode 16, respectively. Apower source 26 is connected in the middle of either the connecting wire27 or the connecting wire 28.

With a substrate plating apparatus as described above, the currentflowing between the cathode 16 and anode 17 is the same as the current Iflowing between the semiconductor wafer 12 and anode 13. Accordingly, anamount of Cu²⁺ ions equivalent to the amount consumed in the platingbaths 11 is supplied from the circulating vessel or dummy vessel 10.

In the substrate plating apparatus shown in FIGS. 2-4, the liquidcontact area of the selective ion exchange film disposed between thecathode 16 and anode 17 must of course be adjusted based on the type ofions used. As described on page 5 of the Plating Manual (Mekki Kyohon)by the Electroplating Society (Nikkan Kogyo Shinbun, Ltd.), the speed ofions in liquid differs as shown below, depending on whether the ions areH⁺, Cu²⁺, or SO₄ ²⁻.

Moving Speed of Ions in Aqueous Solution at 18° C.

Cation selective exchange film H⁺ 31.5 μm/s Cu²⁺  2.9 μm/s Anionselective exchange film SO₄ ²⁻ 5.93 μm/s

The moving speeds indicated above were measured by applying a voltage of1 V between electrodes spaced 1 centimeter apart.

In the embodiment described above, the soluble anode 17 is formed ofcopper and generates Cu²⁺ ions, and a copper plating process isconducted on the semiconductor wafer 12. However, the present inventionis not limited to conducting copper plating in the plating baths 11, butcan be applied to other types of metal plating. When performing adifferent type of metal plating, the soluble anode 17 should be a metalanode that emits positive metallic ions corresponding to the type ofmetal plating to be performed.

Further, the substrate in the present embodiment is not limited to asemiconductor wafer, but can apply to any substrate capable of beingplated.

A substrate plating apparatus according to the first embodiment of thepresent invention has the following remarkable advantages.

By replenishing the plating bath with metallic ions generated from thesoluble anode in the circulating vessel or dummy vessel providedseparately from the plating supply vessel, not only is it possible toautomatically supply metallic ions, but it is no longer necessary toreplace the anode in the plating supply vessel regularly or takemeasures against black film on the surface of the anode.

By making the current flowing between the anode and cathode in thecirculating vessel or dummy vessel equal to the total current flowingbetween substrates and insoluble anodes in the plating baths,maintenance need only be conducted on the soluble anode in onecirculating vessel or dummy vessel.

Further, by making the current flowing between the anode and cathode ofthe circulating vessel or dummy vessel equal to the current flowingbetween the anode and cathode of the plating bath, it is possible tosupply an amount of metallic ions equal to the amount consumed in theplating bath.

FIG. 5 shows a partial view of a substrate plating apparatus accordingto a second embodiment of the present invention. As shown in thediagram, the substrate plating apparatus includes a positive ionexchange film 108 disposed between the substrate 102 (cathode) and anode103.

As described above, a uniform distribution of the primary current shouldbe provided between the substrate 102 and anode 103 to improveuniformity of the plating thickness on the surface of the substrate 102.In order to attain a uniform primary current distribution, the distancebetween the substrate 102 and the anode 103 should be large. However, inorder to increase the distance between the substrate 102 and anode 103,the substrate plating vessel 101 must also be large. Here, disposing thepositive ion exchange film 108 between the substrate 102 and anode 103is equivalent to increasing the distance between the substrate 102 andanode 103. The positive ion exchange film 108 divides the substrateplating vessel 101 into two regions, that is, the region near thesubstrate 102 and the region near the anode 103.

With regard to the distance between the substrate 102 and anode 103 inthe apparatus shown in FIG. 5 at L₂ and the distance between thesubstrate 102 and anode 103 in the apparatus of the prior art, which isnot provided with a positive ion exchange film 108, at L₁, the followingrelationship is true even when attaining a uniform distribution of thesame primary current.

L ₁ >>L ₂

In other words, the interval L₂ between the substrate 102 and anode 103in the present invention can be made smaller than the interval L₁ in theprior art to obtain a uniform primary current distribution.

FIG. 6 shows the effects of disposing a positive ion exchange film 108between the substrate 102 and anode 103. As shown in the diagram, a stepis incorporated in the surface of the anode 103. Assuming that thecurrent density at the interval L₁ between the substrate 102 and anode103 is I₁, the current density at the interval L₂ is I₂, the resistanceof the plating solution Q is ρ, and the transmission resistance is R,then: $\begin{matrix}{{i_{2}/i_{1}} = {( {{1_{1}\rho} + R} )/( {{1_{2}\rho} + R} )}} \\ {{{ {= {{\{ {1_{2} + {\Delta \quad 1}} )\rho} + R}} \}/1_{2}}\rho} + R} ) \\{= {1 + {( {\Delta \quad 1\rho} )/( {{1_{2}\rho} + R} )}}}\end{matrix}$

Hence, to achieve a uniform primary current distribution, the currentdensity i₂/i₁ should approach

1. Rather than increasing the distance l₂ between the substrate 102 andanode 103 for this fraction to approach 1, the positive ion exchangefilm 108 is disposed between the substrate 102 and anode 103 to provideelectrical resistance in the plating solution. This achieves the sameeffects. In other words, positioning the ion exchange film 108 betweenthe substrate 102 and anode 103 has the same effects as increasing thedistance between the substrate 102 and anode 103, even when the distanceis not great. This in turn enables the construction of a small substrateplating apparatus.

When the substrate plating apparatus shown in FIG. 5 is a copper platingapparatus for forming a copper plating film on the substrate 102, theanode 103 is a soluble anode, and the plating solution is coppersulfate, if the cation exchange film 108 only allows the passage of Cu²⁺ions dissolved from the anode 103, then the ion exchange film 108 canblock impurities dissolved from the anode 103, drastically reducing thenumber of particles in the liquid near the region of the substrate 102.

While the invention described above employs an ion exchange film 108between the substrate 102 and anode 103, a neutral porous diaphragmemploying a fine particle removing function can be used in place of theion exchange film 108 with the same effects.

The ion exchange film described above can be a commercial product havingthe capability of selectively filtering ions according to theirelectrical property. One such example is “Ceremion” produced by theAsahi Glass Company. The neutral porous diaphragm is a porous filmformed of synthetic resin and having extremely small holes of uniformdiameter. One such example is a product called “YUMICRON” manufacturedby Yuasa Ionics, which has an aggregate of polyester and a film materialformed of polyvinylidene fluoride and titanium oxide.

FIG. 7 is a cross-sectional view showing the basic construction of aplating bath used in the substrate plating apparatus of the presentinvention. As shown in the diagram, a plating bath 41 includes a mainsection 45 and a side plate 46. A depression 44 is formed in the mainsection 45 for accommodating plating solution. A hinge mechanism (notshown) is provided on the lower end of the side plate 46 to enable theopening and closing of the opening to the depression 44. A soluble anode47 is disposed on the surface of a bottom plate 45 a of the main section45 on the side plate 46 side. A substrate 48, such as a semiconductorwafer, for plating is mounted on the main section 45 side surface of theside plate 46. A packing 50 contacts the surface of the substrate 48when the side plate 46 is closed over the opening of the depression 44.The depression 44 is hermetically sealed.

An ion exchange film or neutral porous diaphragm 49 is disposed betweenthe substrate 48 and anode 47 when the side plate 46 is closed over thedepression 44, thereby dividing the depression 44 into a substrateregion 44-1 and an anode region 44-2. An upper header 42 and a lowerheader 43 are provided on the top and bottom of the main section 45,respectively. An opening 42 a in the upper header 42 and an opening 43 ain the lower header 43 are in liquid communication with the substrateregion 44-1.

A plating solution inlet 51 and outlet 52 are formed in liquidcommunication with the top and bottom of the anode region 44-2,respectively. Shutoff valves 55 and 56 are disposed at the ends of theinlet 51 and outlet 52 via filters 53 and 54. The shutoff valves 55 and56 are connected to the openings 42 a and 43 a via pipes 57 and 58respectively. Hence, plating solution entering the substrate region 44-1and anode region 44-2 in the main section 45 is separated externallyfrom the main section 45 before being introduced therein. After exitingthe main section 45, the plating solution is recombined outside the mainsection 45. Further, plating solution entering and exiting the anoderegion 44-2 must pass through the filters 53 and 54. The apparatus shownin FIG. 7 also includes reverse stop valves 59 and 60.

In the plating bath 41 described above, a plating solution Q in the pipe58 is supplied via the opening 43 a to the substrate region 44-1 and viathe shutoff valve 56 and filter 54 to the anode region 44-2.Accordingly, the plating solution Q flows in the direction indicated bythe arrows A through the substrate region 44-1 and anode region 44-2.The plating solution Q in the substrate region 44-1 passes through theopening 42 a and flows out into the pipe 57. The plating solution Q inthe anode region 44-2 flows through the inlet 51, the filter 53, and theshutoff valve 55 and merges with the plating solution Q from thesubstrate region 44-1 flowing in the pipe 57.

In the substrate plating apparatus described above, black film depositedon the surface of the anode 47 produces particles in the platingsolution Q in the anode region 44-2. However, these particles areprevented from being combined with the plating solution Q in thesubstrate region 44-1 because the plating solution Q flowing out of theanode region 44-2 passes through the filter 53 and shutoff valve 55before combining outside of the main section 45 with plating solution Qflowing out of the substrate region 44-1.

Before removing the substrate 48 from the plating bath 41, the platingsolution Q is discharged from the substrate region 44-1. The platingsolution Q in the anode region 44-2 should not be discharged in order toprevent the black film on the surface of the anode 47 from convertinginto white film. Therefore, when removing the substrate 48 from theplating bath 41, the shutoff valve 55 and shutoff valve 56 can be closedto prevent the discharge of plating solution Q from the anode region44-2.

In the embodiment described above, plating solution Q flows in thesubstrate region 44-1 and anode region 44-2 from the bottom of the mainsection 45 to the top. However, it is also possible to configure themain section 45 such that the plating solution Q flows from the top tothe bottom or alternates directions from the top to the bottom and thebottom to the top. Furthermore, a predetermined voltage is appliedbetween the substrate 48 and anode 47.

As described above, the ion exchange film or neutral porous diaphragm 49is disposed between the substrate 48 and anode 47 to achieve theequivalent effect of increasing electrical resistance in the platingsolution Q between the substrate 48 and anode 47. Hence, even if thedistance between the substrate 48 and anode 47 is small it is stillpossible to achieve a uniform primary current distribution between thesubstrate 48 and anode 47, thereby forming a plating film of uniformthickness on the surface of the substrate 48.

If the anode 47 is a soluble electrode, such as a copper plate, and theplating solution Q is copper sulfate solution, then the cation exchangefilm or neutral porous diaphragm 49 allows only the passage of copperions dissolved from the anode 47. As a result, the cation exchange filmor neutral porous diaphragm 49 can block impurities dissolved from theanode 47 and drastically reduce the amount of particles in the platingsolution Q on the side of the substrate 48.

FIG. 8 is a cross-sectional view showing another detailed structure ofthe plating bath for a substrate plating apparatus of the presentinvention. The plating bath 41 of FIG. 8 differs from that in FIG. 7 onthe following points. An insoluble anode 63 is used in place of thesoluble anode 47, while a diaphragm 61 formed of a neutral porousdiaphragm or an ion exchange film is disposed between the anode 63 andsubstrate 48 to divide the plating bath 41 into the substrate region44-1 and the anode region 44-2. Further, a plate 62 is provided incontact with the diaghram 61 and serves as a current shielding plate forgenerating a uniform primary current distribution between the anode 63and substrate 48.

Although not shown in the diagrams, the plating bath 41 is provided withseparate circulating pumps for separately circulating plating solutionin the substrate region 44-1 and in the anode region 44-2.

As described above, a diaphragm 61 formed of a neutral porous diaphragmor ion exchange film is disposed between the anode 63 and substrate 48.Since the fresh plating solution does not contact the surface of theanode 63, the additives are not resolved. As a result, the life of theplating solution Q can be lengthened.

By circulating the plating solution in the substrate region 44-1 andanode region 44-2 using separate circulating pumps, plating solutionflowing through the anode region 44-2 flows separately from platingsolution flowing over the surface of the substrate 48 and flows out ofthe main section 45 together with O₂ gas produced from the surface ofthe anode 63.

Next, the remarkable advantages of the substrate plating apparatusaccording to the present invention will be described.

Providing an ion exchange film or neutral porous diaphragm between thesubstrate and the anode has an equivalent effect to increase theelectrical resistance in the plating solution between the substrate andthe anode. Accordingly, it is possible to achieve a uniform primarycurrent distribution between the substrate and the anode, even if thedistance between the two is small, thereby forming a uniform platingfilm on the surface of the substrate. As a result, manufacturers canattempt to decrease the size of the substrate plating apparatus.

By using a soluble anode and an ion exchange film that only allows thepassage of ions dissolved from the soluble anode, the ion exchange filmcan block impurities dissolved from the anode. Accordingly, theconfiguration can drastically reduce the amount of particles in theplating solution on the side of the substrate.

Further the substrate plating apparatus described above is provided withshutoff valves at the inlet and outlet to the anode region, such thatplating solution in the anode region passes through the shutoff valvebefore combining with plating solution flowing out of the substrateregion. In other words, plating solution in the anode region andsubstrate region are combined outside the plating bath. Accordingly,particles emitted from black film deposited on the anode are notcombined with plating solution in the substrate region.

Further, a filter provided on the outlet to the anode region removesparticles generated in the plating solution from black film deposited onthe anode.

Further, a diaphragm formed of a neutral porous diaphragm or ionexchange film is disposed between the anode and substrate. Accordingly,fresh plating solution does not contact the surface of the anode. As aresult, resolved additives are not introduced into the substrate region,thereby lengthening the life of the plating solution.

By circulating plating solution in the substrate region and the anoderegion using separate circulating devices, the plating solution flowingin the anode region flows separately from that plating solution flowingin the substrate region and discharges externally along with O₂ gasproduced from the surface of the anode.

FIG. 9 shows a third embodiment of the substrate plating apparatusaccording to the present invention. As shown in the diagram, a platingbath 110 contains a main section 111. The main section 111 accommodatesa plating retainer 112 for supporting a substrate 113 such as asemiconductor wafer. The plating retainer 112 comprises a retainingmember 112-1 and a shaft member 112-2. The shaft member 112-2 isrotatably supported on the inner walls of a cylindrical guide member 114via bearings 115. The guide member 114 and plating retainer 112 can beraised and lowered at a predetermined stroke by a cylinder 116 providedat the top of the main section 111.

A motor 118 is provided at the inner top of the guide member 114 forrotating the plating retainer 112 in the direction indicated by thearrow A via the shaft member 112-2. A space C formed in the platingretainer 112 contains a substrate presser 117. The presser 117 comprisesa pressing member 117-1 and a shaft member 117-2. A cylinder 119 isprovided at the inner top of the shaft member 112-2 for moving thepresser 117 up and down at a predetermined stroke.

An opening 112-1 a is provided at the bottom of the retaining member112-1 and is in liquid communication with the space C. A step 112-1 b asshown in FIG. 10 is formed at the top of the opening 112-1 a forsupporting the edge of the substrate 113. By supporting the edge of thesubstrate 113 on the step 112-1 b and applying pressure to the topsurface of the substrate 113 with the pressing member 117-1, the edge ofthe substrate 113 is pinched by the pressing member 117-1 and the step112-1 b. The bottom surface (plating surface of the substrate 113) isexposed in the opening 112-1 a.

A plating solution chamber 120 is provided beneath the retaining member112-1 for enabling the flow of plating solution Q beneath the platingsurface of the substrate 113 exposed in the opening 112-1 a. A platingsolution supply header 121 is disposed on one side of the main section111. A plating solution inlet 122 is formed in the plating solutionsupply header 121 and is in liquid communication with the platingsolution chamber 120. A plating solution outlet 123 is formed in theopposite side of the main section 111 from the plating solution supplyheader 121 to enable the outflow of the plating solution Q. A collectinggutter 124 is provided around the outside of the main section 111 forcollecting plating solution Q flowing out of the outlet 123 (overflowingfrom the plating solution chamber 120).

The plating solution Q collected by the collecting gutter 124 isreturned to a plating solution tank 125. A pump 126 is provided tosupply plating solution Q in the plating solution tank 125 to theplating solution supply header 121. The plating solution Q supplied tothe plating solution supply header 121 flows into the plating solutionchamber 120 from the inlet 122, flows horizontally along and in contactwith the plating surface of the substrate 113, then flows out into thecollecting gutter 124 via the outlet 123. In other words, the platingsolution Q is cycled between the plating solution chamber 120 andplating solution tank 125.

The level of the plating solution surface L_(Q) shown in the diagram isonly slightly higher by a small ΔL than the level L_(W) at the substrate113 in order that the entire plating surface of the substrate 113 iscontacted by plating solution Q. The inlet 122 and outlet 123 aredisposed one on either side of the substrate 113 and outside theperiphery of the substrate 113. The plating solution Q in the platingsolution chamber 120 flows horizontally while contacting the platingsurface of the substrate 113. As shown in FIG. 10, an electrical contact130 is provided for electrically connecting the conducting portion ofthe substrate 113 on the step 112-1 b. The electrical contact 130 isconnected via a brush 127 to the cathode of a power source (not shown)outside of the main section 111. An anode 128 is provided opposite thesubstrate 113 below the plating solution chamber 120. The anode 128 isconnected to the anode of the power source. A slit 129 is formed at apredetermined position in the wall of the main section 111 to facilitateinsertion and removal of the substrate 113 using a substrate transportjig such as a robot arm.

An ion exchange film or neutral porous diaphragm 134 is disposed on thebottom of the plating solution chamber 120. An anode chamber 131 isdisposed beneath the ion exchange film or neutral porous diaphragm 134.The anode 128 is provided on the bottom of the anode chamber 131.Plating liquid or conductive liquid Q′ is introduced from the anodechamber 131 into the plating solution chamber 120 via the ion exchangefilm or neutral porous diaphragm 134. A liquid tank 133 contains theplating solution or conductive liquid Q′ and a pump 132 supplies theplating solution or conductive liquid Q′ in the liquid tank 133 to theanode chamber 131. After flowing through the anode chamber 131 theplating solution or conductive liquid Q′ is recycled to the liquid tank133. In other words, plating solution or conductive liquid Q′ is cycledbetween the anode chamber 131 and liquid tank 133.

Next, the plating operations will be described for a plating apparatushaving the construction described above. First, the cylinder 116 isactivated, moving the plating retainer 112 and guide member 114 upward apredetermined amount (to a position in which the substrate 113 supportedby the retaining member 112-1 corresponds to the slit 129). At the sametime, the cylinder 119 is activated to move the presser 117 up apredetermined amount (such that the pressing member 117-1 contacts thetop of the slit 129). At this time, a robot arm or other substratetransporting jig inserts a substrate 113 into the space C of the platingretainer 112. The substrate 113 is placed on the step 112-1 b with itsplating surface facing downward. The cylinder 119 is again driven tomove the presser 117 until the bottom of the surface of the pressingmember 117-1 contacts the top surface of the substrate 113, effectivelypinching the edge of the substrate 113 between the pressing member 117-1and the step 112-1 b.

At this time, the cylinder 116 is operated to move the plating retainer112 and guide member 114 downward until the plating surface of thesubstrate 113 contacts the plating solution flowing through the platingsolution chamber 120 (or until the bottom surface of the substrate 113is just ΔL lower than the lever of the plating solution surface L_(Q)).Next, the motor 118 is driven to move the plating retainer 112 andsubstrate 113 downward while rotating them at a slow speed. As describedabove, plating solution Q is supplied from the plating solution tank 125to the plating solution chamber 120 by means of the pump 126 andcirculated in this manner. During this time, the power source applies apredetermined voltage between the anode 128 and electrical contact 130to create a plating current from the anode 128 to the substrate 113 andform a plating film on the plating surface of the substrate 113.

During the plating process, the motor 118 drives the plating retainer112 and substrate 113 to rotate at the low speed of 1-10 rpm. Byrotating the substrate 113 at this low rotational speed, it is possibleto avoid causing adverse effects to the flow of the plating solution Qin the plating solution chamber 120 (level to the plating surface of thesubstrate 113), that is, to avoid disturbing the uniform relative speedbetween the plating surface and plating solution. The rotation alsoeliminates differences in film thickness generated on the upstream anddownstream sides of the flow of plating solution to form a plating filmof uniform thickness on the plating surface of the substrate 113.

When the plating process is completed, the cylinder 116 is driven tomove the plating retainer 112 and substrate 113 upward until the bottomsurface of the retaining member 112-1 is above the plating solutionlevel L_(Q). At this point, the motor 118 spins the plating retainer 112and substrate 113 at a high speed to shake off plating solutiondeposited on the plating surface of the substrate and bottom surface ofthe retaining member 112-1 using centrifugal force. After shaking offthe plating solution, the substrate 113 is raised until positioned atthe slit 129. Next, the cylinder 119 is operated to raise the pressingmember 117-1, releasing the substrate 113 such that the substrate 113rests on the step 112-1 b. Here, the robot arm or other substratetransport jig is inserted in the space C of the plating retainer 112,and picks up and removes the substrate 113 from the slit 129.

As described above, the anode chamber 131 is disposed beneath the inlet122 and separated from the same by the ion exchange film or neutralporous diaphragm 134. Plating liquid or conductive liquid Q′ is flowedthrough the anode chamber 131. With this configuration, it is possibleto prevent resolution of additives from oxidizing on the surface of theanode 128 when using an insoluble anode 128. Further, oxide gasgenerated from the surface of the anode 128 is blocked by the ionexchange film or neutral porous diaphragm 134 and prevented fromreaching the plating surface of the substrate 113. Accordingly, thisconstruction can prevent unusual consumption of additives in the platingsolution Q, as well as the formation of fine holes and channels in theplating surface of the substrate caused by oxygen gas and the generationof plating defects in the surface.

With the construction described above, the plating solution Q flowsthrough the plating solution chamber 120 level to the plating surface ofthe substrate 113. This method enables the plating bath 110 to beproduced with a smaller depth than plating baths using the conventionalface down method that shoots a plating solution jet directly at thesubstrate. Accordingly, a plurality of plating baths 110 can be providednext to each other.

As described above, a flattened plating solution chamber is providedbelow the plating surface of the substrate and a plating solution inletfor allowing plating solution to flow into the plating solution chamberand a plating solution outlet to enable plating solution to flow out ofthe chamber are provided on either side of the substrate and outside theperiphery of the substrate. With this configuration, plating in theplating solution chamber flows level and in contact with the platingsurface of the substrate. Accordingly, the relative speed of the platingsolution to the plating surface is uniform across the entire surface ofthe substrate. Additives in the plating solution are uniformly adsorbed,improving implanting properties for fine holes and channels in thesubstrate to achieve a uniform plating thickness. Further, since theplating solution flows level to the plating surface on the bottom of thesubstrate, the depth of the plating bath can be made small.

Also, an anode chamber is provided below the plating solution chamberand separated from the plating solution chamber by an ion exchange filmor neutral porous diaphragm, through which plating solution or anotherconductive liquid flows. This configuration prevents the surface of theanode from being oxidized and prevents unusual consumption of additivesin the plating solution. Further, oxygen gas generated from the surfaceof the anode is prevented by the ion exchange film or neutral porousdiaphragm from reaching the substrate. Accordingly, this configurationcan prevent defects of plating layer from forming plating in fine holesand channels in the surface of the substrate.

By providing a mechanism for rotating the substrate, the substrate canbe rotated in the plating solution at a slow speed with the platingsurface facing downward to form a plating film of uniform thickness onthe substrate. After the plating is completed, the substrate can beraised out of the plating solution and rotated at a fast speed to shakeoff excess plating solution into the plating bath, thereby reducing theamount of contamination from plating solution on the outside of theplating bath.

Further, the overall surface configuration of the plating apparatus canbe made smaller by providing a plurality of plating baths in a stage.Hence, it is possible to reduce the required installation space.

FIG. 11 shows another embodiment of a plating bath according to thepresent invention. As shown in the diagram, the structure from platingretainer 112 and above is the same as that in FIG. 9. Therefore, adescription of that section will be omitted. A flattened platingsolution chamber 120 is provided below the retaining member 112-1, thatis, below the plating surface of the substrate 113 exposed from theopening 112-1 a. A flat plating-solution introducing chamber 122 isdisposed beneath the plating solution chamber 120. A porous plate 121having a plurality of pores 121 a separates the plating solution chamber120 from the plating-solution introducing chamber 122. A collectinggutter 123 provided around the plating solution chamber 120 collectsplating solution Q that overflows from the plating solution chamber 120.

Plating liquid Q collected from the plating solution chamber 120 isreturned to the plating solution tank 125. The pump 126 pumps platingsolution Q from the plating solution tank 125 and introduces ithorizontally from both sides into the plating-solution introducingchamber 122. After being introduced into both sides of theplating-solution introducing chamber 122, the plating solution Q flowsinto the plating solution chamber 120 via the pores 121 a formed in theporous plate 121 becoming jets perpendicular to the substrate 113. Thedistance between the substrate 113 and the porous plate 121 is 5-15 mm.The jet streams of plating solution Q forced through the pores 121 a aremaintained in a uniform upward direction to contact the plating surfaceof the substrate 113. Plating solution Q that overflows from the platingsolution chamber 120 is collected by the collecting gutter 123 andreturned to the plating solution tank 125. In other words, platingsolution Q is circulated between the plating solution chamber 120 andthe plating solution tank 125.

The plating bath 110 is further provided with the anode chamber 131below the plating-solution introducing chamber 122 for introducingplating solution or conductive liquid Q′ into the plating-solutionintroducing chamber 122 via an ion exchange film or neutral porousdiaphragm 130 and the anode 128 on the bottom of the anode chamber 131.The pump 132 introduces plating solution or conductive liquid Q′ fromthe liquid tank 133 into the anode chamber 131. After flowing throughthe anode chamber 131, the plating solution or conductive liquid Q′ isreturned to the liquid tank 133. In other words, plating solution orconductive liquid Q′ is circulated between the anode chamber 131 and theliquid tank 133.

As described above, the anode chamber 131 is disposed beneath theplating-solution introducing chamber 122 and separated from the same bythe ion exchange film or neutral porous diaphragm 130. Plating liquid orconductive liquid Q′ is flowed through the anode chamber 131. With thisconfiguration, it is possible to prevent oxidation on the surface of theanode 128 when using an insoluble anode 128. Further, oxide gasgenerated from the surface of the anode 128 is blocked by the ionexchange film or neutral porous diaphragm 130 and prevented fromreaching the plating surface of the substrate 113. Accordingly, thisconstruction can prevent unusual consumption of additives in the platingsolution Q, as well as the defects by formation of plating layer at fineholes and channels in the plating surface of the substrate caused byoxygen gas.

As described above, the plating bath is provided with a plating solutionchamber formed between the substrate and the porous plate opposite andseparated a predetermined distance below the substrate; and a flattenedplating-solution introducing chamber formed below the porous plate. Theplating solution flows horizontally into the plating-solutionintroducing chamber and is forced through the plurality of holes in theporous plate to form flows of plating solution perpendicular to theplating surface of the substrate. Accordingly, by appropriately settingthe distance between the porous plate and the substrate, it is possibleto form a flattened plating bath with a shallow depth, without requiringto increase the distance above the plating solution or to rectify theflow.

An anode chamber is provided below the plating-solution introducingchamber and separated from the introducing chamber by an ion exchangefilm or neutral porous diaphragm. Plating solution or another conductiveliquid is flowed through the anode chamber. This configuration preventsthe anode surface from being oxidized and prevents the unusualconsumption of additives in the liquid. Further, generated oxygen gas isblocked by the ion exchange film or neutral porous diaphragm andprevented from contacting the substrate, thereby preventing defectsbeing formed in the plating layer at fine holes and channels in thesurface of the substrate.

By providing a mechanism for rotating the substrate in the platingsolution at a slow speed with the plating surface facing downward, theplating surface of the substrate is uniformly contacted by platingsolution to form a plating film of uniform thickness on the substrate.After the plating process is completed, the mechanism lifts thesubstrate out of the plating solution and rotates the substrate at afast speed to shake off excess plating solution into the plating bath,thereby reducing the amount of contamination from plating solution onthe outside of the plating bath.

By setting the distance between the substrate and porous plate at 5-15mm, the rotation of the substrate forces liquid toward the periphery ofthe substrate by the viscosity of the liquid. This effect lowers thepressure toward the center of the substrate and increases the flow ofliquid through the center of the porous plate, thereby achieving auniform vertical component of velocity over the entire surface of thesubstrate. Accordingly, it is possible to produce a plating bath with ashallow depth, since there is no need to increase the depthwise distancefor the ascending liquid current as in the prior art.

The footstep of the overall apparatus can be decreased by providing aplurality of plating baths next to one another in a stage, therebyreducing the amount of space required for installation.

FIGS. 12A and 12B show the overall structure of a plating apparatusemploying the plating baths 110 described above. FIG. 12A is a plan viewof the apparatus, while FIG. 12B is a side view. As shown the diagrams,a plating apparatus 140 comprises a loading section 141, an unloadingsection 142, cleaning and drying vessels 143, a loading stage 144, acoarse washing vessel 145, plating stages 146, preprocess vessesl 147, afirst robot 148, and a second robot 149. Each of the plating stages 146includes a combination of two plating baths 110 as configured in FIG. 9or FIG. 11. Hence, the entire plating apparatus is provided with fourplating baths 110. This construction is possible because the platingbath 110 has a more shallow depth than the plating bath of the priorart.

With the plating apparatus 140 described above, substrates 113 arecontained in a cassette deposited on the loading section 141. The firstrobot 148 extracts one substrate 113 at a time and transfers it to theloading stage 144. Here, the second robot 149 transfers the substrate113 at the loading stage 144 to one of the preprocess vessels 147, wherethe substrate 113 is preprocessed. Next, the second robot 149 transfersthe preprocessed substrate 113 to a plating bath 110 in one of theplating stages 146, where the substrate 113 undergoes a plating process.After the plating process is completed, the second robot 149 transfersthe substrate 113 to the coarse washing vessel 145 for washing. Next,the first robot 148 transfers the substrate 113 to the cleaning anddrying vessels 143 to be washed and dried, after which the first robot148 transfers the substrate 113 to the unloading section 142.

Since the plating bath 110 of the present invention is provided with aplating solution chamber 120 beneath the plating surface of thesubstrate 113 through which plating solution Q flows horizontally acrossthe plating surface, the depth of the plating bath 110 can be shallow,enabling a plurality (two in this case) of plating baths 110 to beprovided together. The installation space of the entire platingapparatus can be decreased since the depth of two plating baths 110 isequivalent to one plating bath using the face down method of the priorart. In other words, when using plating baths of the prior art toconstruct a plating apparatus with four plating baths, only one platingbath can be provided in each plating stage 146. Therefore, theinstallation area required for the plating stages 146 would be twice aslarge as that shown in FIG. 12B.

While the invention has been described in detail with reference tospecific embodiments thereof, it would be apparent to those skilled inthe art that many modifications and variations may be made thereinwithout departing from the scope of the invention, the scope of which isdefined by the attached claims. For example, the embodiments describedabove used electrolytic plating in the plating apparatus of the presentinvention, but the present invention can also apply to an apparatusconducting electroless plating. In addition to using copper sulfateplating solution for the plating solution Q to conduct copper plating,it is also possible to use other plating solution to conduct a platingprocess with a different metal.

Industrial Applicability

The present invention is applicable to the semiconductor industry, sincethe substrate plating can be conducted so as to form a fine wiring layeron a semiconductor wafer.

What is claimed is:
 1. A substrate plating apparatus for plating asubstrate in a plating bath containing a plating solution when an anodeis disposed in the plating bath opposite the substrate, the substrateplating apparatus comprising: an ion exchange film or neutral porousdiaphragm to be disposed between the substrate and anode in the platingbath for dividing the plating bath into a substrate region and an anoderegion; and shutoff valves to serve as an inlet and outlet for platingsolution in the anode region, wherein plating solution from the anoderegion is to flow through one of the shutoff valves and merge withplating solution flowing from the substrate region.
 2. The substrateplating apparatus according to claim 1, wherein the anode is a solubleanode and the ion exchange film is a cationic exchange film throughwhich only ions dissolved from the soluble anode can pass.
 3. Thesubstrate plating apparatus according to claim 1, further comprising afilter in fluid communication with the one of the shutoff valves forfiltering plating solution flowing from the anode region.
 4. A substrateplating apparatus for plating a substrate in a plating bath containing aplating solution when an insoluble anode is disposed in the plating bathopposite the substrate, the substrate plating apparatus comprising: adiaphragm formed of an ion exchange film or neutral porous diaphragm tobe disposed between the substrate and the insoluble anode in the platingbath for dividing the plating bath into a substrate region and an anoderegion; and a plate that contacts the ion exchange film or neutralporous diaphragm and is to serve as a shielding plate for correctingprimary current distribution between the insoluble anode and substrate.5. The substrate plating apparatus according to claim 4, furthercomprising circulating devices for separately circulating the platingsolution in the substrate region and anode region.
 6. A substrateplating apparatus for plating a substrate in a plating bath containingplating solution when an anode is disposed in the plating bath oppositethe substrate, the plating apparatus comprising: an ion exchange film orneutral porous diaphragm to be disposed between the substrate and anodein the plating bath, whereby the ion exchange film or neutral porousdiaphragm is to divide the plating bath into a substrate region and ananode region; a plating solution chamber to be disposed under a platingsurface of the substrate when the substrate is disposed with its platingsurface facing downward; a plating solution inlet and plating solutionoutlet to be disposed in opposition to each other one on either side ofthe periphery of the substrate, with the plating solution inlet enablingan inflow of plating solution into the plating solution chamber and theplating solution outlet enabling an outflow of plating solution from theplating solution chamber, such that plating solution in the platingsolution chamber can flow parallel to and in contact with the platingsurface of the substrate; an anode chamber provided under the platingsolution chamber via the ion exchange film or neutral porous diaphragm,with plating solution or another conductive liquid to flow in the anodechamber; and an anode disposed at the bottom of the anode chamber tooppose the substrate via the ion exchange film or neutral porousdiaphragm.
 7. The substrate plating apparatus according to claim 6,further comprising a substrate rotating mechanism for rotating thesubstrate while the plating surface of the substrate faces downward inthe plating bath.
 8. The substrate plating apparatus according to claim7, wherein the substrate is to be rotated by the substrate rotatingmechanism in the plating bath at a speed of 1-10 rpm.
 9. The substrateplating apparatus according to claim 6, further comprising a platingstage to be provided with a plurality of plating baths.
 10. A substrateplating apparatus for plating a substrate in a plating bath containingplating solution when an anode is disposed in the plating bath oppositethe substrate and the substrate has its plating surface facing downward,the plating apparatus comprising: an ion exchange film or neutral porousdiaphragm to be disposed between the substrate and anode in the platingbath, whereby the ion exchange film or neutral porous diaphragm is todivide the plating bath into a substrate region and an anode region; aplating solution chamber to be formed between the substrate and the ionexchange film or neutral porous diaphragm; a porous plate having aplurality of holes; a plating solution introducing chamber formed belowthe porous plate, wherein plating solution is to be introduced into theplating solution introducing chamber in a horizontal direction andforced through the holes in the porous plate to form flows orthogonal tothe plating surface of the substrate; an anode chamber provided underthe plating solution chamber via the ion exchange film or neutral porousdiaphragm; and an anode disposed at the bottom of the anode chamber tooppose the substrate via the ion exchange film or neutral porousdiaphragm and the porous plate, wherein the plating solution or anotherconductive liquid is to flow in the anode chamber.
 11. The substrateplating apparatus according to claim 10, further comprising a substraterotating mechanism for rotating the substrate while the plating surfaceof the substrate faces downward in the plating bath.
 12. The substrateplating apparatus according to claim 10, wherein the distance betweenthe substrate and the porous plate is to be 5-15 mm.
 13. The substrateplating apparatus according to claim 10, further comprising a platingstage to be provided with a plurality of plating baths.
 14. A substrateplating apparatus for plating a substrate, comprising: a plating bathcapable of containing a plating solution when an insoluble anode isdisposed in the plating bath opposite a plating surface of a substratewhen the substrate is disposed with the plating surface facing downward;and a circulating vessel or dummy vessel provided separate from theplating bath, with a soluble anode and a cathode being disposed in thecirculating vessel or dummy vessel, and an anion exchange film orselective cation exchange film being disposed between the soluble anodeand the cathode for isolating the soluble anode and cathode, whereinmetal ions are to be generated in the circulating vessel or dummy vesselby flowing current between the soluble anode and the cathode, and thegenerated metal ions are to be supplied to the plating bath.
 15. Thesubstrate plating apparatus according to claim 14, further comprising asulfuric acid source to supply sulfuric acid so as to maintain liquid ata uniform conductivity in the circulating vessel or dummy vessel. 16.The substrate plating apparatus according to claim 15, furthercomprising a substrate rotating mechanism for rotating the substratewhile the plating surface of the substrate faces downward in the platingbath.
 17. The substrate plating apparatus according to claim 15, furthercomprising a plating stage provided with a plurality of plating baths.18. The substrate plating apparatus according to claim 14, furthercomprises a plurality of plating baths, and an amount of current to beflowed between the substrate and the insoluble anode in each of theplating baths is to be equal to an amount of current flowed between thesoluble anode and the cathode in the circulating vessel or dummy vessel.19. The substrate plating apparatus according to claim 14, wherein theinsoluble anode in the plating bath is to be connected to the cathode inthe circulating vessel or dummy vessel when the substrate in the platingbath is connected to the soluble anode in the circulating vessel ordummy vessel, and the current to be flowed between the insoluble anodeand the substrate in the plating bath is equal to the current to beflowed between the soluble anode and the cathode in the circulatingvessel or dummy vessel.
 20. A substrate plating apparatus for plating asubstrate, comprising: a plating bath to contain a plating solution whenan anode is disposed in the plating bath opposite a substrate and thesubstrate is disposed with its plating surface facing downward; and anion exchange film or neutral porous diaphragm to be disposed between thesubstrate and the anode in the plating bath, whereby the ion exchangefilm or neutral porous diaphragm is to divide the plating bath into asubstrate region and an anode region.
 21. The substrate platingapparatus according to claim 20, wherein the anode is a soluble anodeand the ion exchange film is a cationic exchange film through which onlyions dissolved from the soluble anode can pass.
 22. The substrateplating apparatus according to claim 20, further comprising shutoffvalves to serve as an inlet and outlet for plating solution in the anoderegion, wherein plating solution from the anode region is to flowthrough one of the shutoff valves and merge with plating solutionflowing from the substrate region.
 23. The substrate plating apparatusaccording to claim 22, further comprising a filter in fluidcommunication with the one of the shutoff valves.
 24. A substrateplating apparatus for plating a substrate, comprising: a plating bath tocontain a plating solution when an insoluble anode is disposed in theplating bath opposite a substrate and the substrate is disposed with itsplating surface facing downward; and an ion exchange film or neutralporous diaphragm to be disposed between the substrate and the insolubleanode in the plating bath, whereby the ion exchange film or neutralporous diaphragm is to divide the plating bath into a substrate regionand an insoluble anode region.
 25. The substrate plating apparatusaccording to claim 24, further comprising a plate that contacts the ionexchange film or neutral porous diaphragm and is to serve as a shieldingplate for correcting primary current distribution between the insolubleanode and substrate.
 26. The substrate plating apparatus according toclaim 24, further comprising circulating devices for separatelycirculating the plating solution in the substrate region and theinsoluble anode region.
 27. The substrate plating apparatus according toclaim 24, wherein plating bath comprises: a plating solution chamber tobe disposed under the plating surface of the substrate; a platingsolution inlet and plating solution outlet to be disposed in oppositionto each other one on either side of the periphery of the substrate, withthe plating solution inlet enabling an inflow of plating solution intothe plating solution chamber and the plating solution outlet enabling anoutflow of plating solution from the plating solution chamber, such thatplating solution in the plating solution chamber can flow parallel toand in contact with the plating surface of the substrate; an anodechamber provided under the plating solution chamber via the ion exchangefilm or neutral porous diaphragm, wherein plating solution or anotherconductive liquid is to flow in the anode chamber; and an anode disposedat the bottom of the anode chamber to oppose the substrate via the ionexchange film or neutral porous diaphragm.
 28. The substrate platingapparatus according to claim 24, further comprising a substrate rotatingmechanism for rotating the substrate while the plating surface of thesubstrate faces downward in the plating bath.
 29. The substrate platingapparatus according to claim 28, wherein the substrate is to be rotatedby the substrate rotating mechanism in the plating bath at a speed of1-10 rpm.
 30. The substrate plating apparatus according to claim 24,further comprising a plating stage provided with a plurality of platingbaths.
 31. The substrate plating apparatus according to claim 24,wherein the plating bath comprises: a plating solution chamber to beformed between the substrate and the ion exchange film or neutral porousdiaphragm; a porous plate having a plurality of holes; a platingsolution introducing chamber formed below the porous plate, whereinplating solution is to be introduced into the plating solutionintroducing chamber in a horizontal direction and forced through theholes in the porous plate to form flows orthogonal to the platingsurface of the substrate; an anode chamber provided under the platingsolution chamber via the ion exchange film or neutral porous diaphragm;and an anode disposed at the bottom of the anode chamber to oppose thesubstrate via the ion exchange film or neutral porous diaphragm and theporous plate, wherein plating solution or another conductive liquid isto flow in the anode chamber.
 32. A substrate plating apparatus forplating a substrate, comprising: a loading section for loading asubstrate; a robot for conveying the substrate; a plating bath capableof containing plating solution when an anode is disposed in the platingbath opposite the substrate; a circulating vessel or dummy vesselprovided separate from the plating bath, with a soluble anode and acathode being disposed in the circulating vessel or dummy vessel, and ananion exchange film or selective cation exchange film being disposedbetween the soluble anode and the cathode for isolating the solubleanode and the cathode, wherein metal ions are to be generated by flowingcurrent between the soluble anode and the cathode, and the generatedmetal ions are to be supplied to the plating bath; a coarse washingvessel for coarsely washing the substrate after a plating process iscompleted; and a cleaning and drying vessel for cleaning and drying thesubstrate after coarse washing of the substrate is completed.
 33. Asubstrate plating apparatus for plating a substrate, comprising: aloading section for loading a substrate; a robot for conveying thesubstrate; a plating bath capable of containing plating solution when ananode is disposed in the plating bath opposite the substrate; an anionexchange film or selective cation exchange film to be disposed betweenthe anode and the substrate for isolating the anode and the substrate; acoarse washing vessel for coarsely washing the substrate after a platingprocess is completed; and a cleaning and drying vessel for cleaning anddrying the substrate which is plated in the plating bath.
 34. Asubstrate plating apparatus for plating a substrate, comprising: aloading section for loading a substrate; a robot for conveying thesubstrate; a plating bath capable of containing plating solution when aninsoluble anode is disposed in the plating bath opposite the substrate;an anion exchange film or selective cation exchange film to be disposedbetween the insoluble anode and the substrate for isolating theinsoluble anode and the substrate; a coarse washing vessel for coarselywashing the substrate after a plating process is completed; and acleaning and drying vessel for cleaning and drying the substrate aftercoarse washing of the substrate is completed.